The first thing that came to my mind is...how many complaints do they get against bottled water? I actually Googled that question, but found nothing yet.

One thing I learned from my time answering questions is that there are a small percentage of folks who come up with some really "interesting" side effects from the most tried and tested products. I've literally had people tell me that creatine caused their big toe to swell, and it lead to a nail infection.

I'm sure some of the claims are legitimate, but I also would wager a high percentage are unrelated or from inappropriate usage. I might be wrong.